NAVLE Diagnostic Imaging Interpretation 4

Question 1

Which finding on thoracic radiographs of a cat is MOST suggestive of hypertrophic cardiomyopathy (HCM)?

Accepted Answer

Valentine-shaped heart on VD view with left atrial enlargement

Answer

HCM in cats classically produces a Valentine or bivalve-shaped cardiac silhouette on the VD view due to biatrial enlargement.

Question 2

On abdominal radiographs, retroperitoneal effusion is BEST identified by:

Accepted Answer

Loss of renal and sublumbar muscle detail with preserved peritoneal serosal detail

Answer

Retroperitoneal effusion selectively obliterates retroperitoneal structures (kidneys, sublumbar muscles) while intraperitoneal serosal detail (bladder, gut) may remain visible.

Question 3

What is the significance of 'air bronchograms' on thoracic radiographs?

Accepted Answer

Air-filled bronchi are visible because surrounding alveoli are fluid-filled, indicating alveolar disease

Answer

Air bronchograms occur when alveolar consolidation or fluid makes normally invisible air-filled bronchi visible by contrast.

Question 4

On ultrasound of the urinary bladder, a non-shadowing, gravity-dependent echogenic material that shifts with patient repositioning is MOST consistent with:

Accepted Answer

Cystic calculi too small to shadow (sludge/crystalluria)

Answer

Fine echogenic material that is gravity-dependent and moves freely with repositioning but does not shadow is consistent with fine crystalluria or bladder sludge.

Question 5

In nuclear scintigraphy, a 'cold spot' on a thyroid scan in a dog MOST likely represents:

Accepted Answer

Nonfunctional or necrotic tissue within the thyroid

Answer

A cold (photopenic) area on thyroid scintigraphy indicates reduced radionuclide uptake, consistent with nonfunctional, necrotic, or cystic tissue.

NAVLE - North American Veterinary Licensing Examination Practice Test

NAVLE - North American Veterinary Licensing Examination Practice Test

NAVLE Diagnostic Imaging Interpretation 4